Step 1: Make sure you select the folder were you would like to upload the file(s) in the left pane;
Step 2: Navigate to Upload files you can add (additional) documents to your Vault;
Step 3: Drag and drop your files and wait until the checkmark is visible;
Step 4: Select Next;
Step 5: Set the permissions;
Step 6: Select Next;
Step 7: Select Upload to complete the uploading wizard.